Thiocarbamate-Directed Tandem Olefination–Intramolecular Sulfuration of Two <i>Ortho</i> C–H Bonds: Application to Synthesis of a COX-2 Inhibitor

Abstract

A palladium-catalyzed dual ortho C-H bond activation of aryl thiocarbamates is developed. This tandem reaction initiates by thiocarbamate-directed ortho C-H palladation, which leads to favorable olefin insertion rather than reductive elimination. The oxidative Heck reaction followed by another C-H activation and sulfuration affords the dual-functionalized products. This reaction provides a concise route to the S,O,C multisubstituted benzene skeleton which could be successfully applied for the synthesis of a COX-2 inhibitor.